In the electronic industry it is widely known that certain electrical or electronic components are susceptible to adverse interferences from adjacent components. Many components generate interference in the form of electromagnetic radiation. This electromagnetic interference (EMI) can adversely affect the operation of certain other components which are positioned in close proximity thereto.
The problem is particularly acute with certain components referred to as baluns. A balun is a device which serves as a transformer for connecting balanced twisted pair cables to unbalanced coaxial or twinaxial cables by matching the electrical impedance characteristics of the two types of cables. Baluns effectively provide an electrical conversion between coaxial/twinaxial cable and twisted pair cable. Electromagnetic "noise" as a result of electromagnetic radiation from electrical components may adversely affect adjacent transmission line components such as the coaxial/twinaxial cable, the twisted pair cable and the balun. Also, the balun itself generates EMI which could adversely affect the operation of components adjacent thereto. In order to reduce the adverse effects of EMI, balun components must be effectively shielded.
It is known to employ within a balun, shielded components, such as electrical connectors or cables so as to shield the individual cable terminations. Such shielded components may include a shielded RJ45 connector, shielded multiconductor cables or shielded coaxial connectors. The baluns additionally provide for shield continuity between the shields of the individual components. Such shield continuity is typically provided by an electrical circuit assembly supported between the two components, such circuit assembly providing both the impedance matching between the two cables as well as a shield continuity.
However, in the present day electronic environment where an increasing number of electronic components are used in close proximity and where the electrical frequency of such components are increasing, the discrete shielding provided by the components in many baluns of the prior art has been found to be inadequate. This shielding insufficiency is especially prevalent in the area between the individual shielded components housed within the balun structure. At this location, shielding is either nonexistent or ineffective.
It is therefore desirable to provide a fully shielded housing assembly for supporting components of a balun. The shielded housing assembly would provide complete shielding for the components of the balun.